A lot has been discussing the loyalty of land-based position machines. A great report by Bob Bourie is named, "Are Position Products Sincere?" and actually seemed in the 1999 American Casino Guide.
It are available on line by searching for the subject in Google or Google!. Physical, land-based slot devices have plenty of "variations" being polite than can deceive the player. Obviously, they're all illegal and do not happen. But read the content, closely.